Gas burners are well-known and are used in a wide variety of applications. A typical gas burner may include a burner bar in, the form of a conduit having a gas inlet and one or more openings along its length to provide gas outlets through which the gas is emitted, prior to combustion. The gas is emitted in the form of jets, which are ignited to produce heat. For most domestic applications, natural gas (a “second family” gas) is used as the fuel, although “third family” gases such as liquid petroleum gas (LPG), butane and propane may also be used. Using these types of gas can require that a large amount of air be available to ensure complete combustion, and this has led to the use of a “pre-aeration” stage in conventional gas burners, typically comprising a short tube in which the air and gas are mixed before the mixture is emitted through the gas outlets. Although this pre-aeration stage helps to achieve complete combustion of the gas, it adds to the cost and complexity of manufacturing gas burners.
In an attempt to overcome this problem, the technology of neat gas burners has been used. In such burners, no pre-aeration chamber or process are used, upstream of the area of combustion, and thus neat gas burners can be cheaper and simpler to manufacture.
This type of burner was originally developed to burn “first family” town gas, which is derived from coal, and which does not require as much air as second and third family gases for complete combustion. In adapting this type of burner to use second and third family gases, it was found that there was insufficient air present for complete combustion to occur. To alleviate this, neat gas burners for second and third family gases have tended to include a baffle near the gas outlets such that gas escaping from the outlets is deflected by the baffle, resulting in turbulence, which causes the gas to mix with the surrounding air. The mixture of gas and air is ignited at the point where the gas hits the baffle, resulting in combustion of the gas.